# Spring gRPC SecurityContext leaks across requests upon authorization failure

Advisory record · `GHSA-4g9c-3x4p-mfpp`

- **Identifiers:** `GHSA-4g9c-3x4p-mfpp` · `CVE-2026-40968`
- **State:** Confirmed
- **Severity:** CVSS 4.3 Medium
- **Critical:** No
- **Weakness (CWE):** [CWE-653](https://cwe.mitre.org/data/definitions/653.html)
- **Tags:** [CWE-653](https://agentprime.io/advisories/tag/cwe-653.md)
- **Published:** 28 Apr 2026
- **Updated:** 6 May 2026
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 28 Apr 2026, 15:30 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Affected packages

- `org.springframework.grpc:spring-grpc` (Maven): affected `<1.0.3`; fixed in `1.0.3`

## Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

> Spring gRPC versions before 1.0.3 are vulnerable. When an authenticated user is denied access to a gRPC method, their identity can remain bound to the worker thread and be inherited by a later unauthenticated request on that same thread, possibly granting it elevated permissions. Upgrade to spring-grpc 1.0.3 or later.

Written 3 Nov 2026.

## Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

## Severity and exploitation

- 4.3 Medium, CVSS 3.1: `CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N`, from CNA (vmware)

- **CISA KEV:** Not listed.
- **EPSS:** 0.0017, the 6th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 31 Oct 2026, 14:20 UTC: First seen by agentprime
- 31 Oct 2026, 14:20 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-4g9c-3x4p-mfpp)

## Sources

- [GitHub Advisory Database: GHSA-4g9c-3x4p-mfpp](https://github.com/advisories/GHSA-4g9c-3x4p-mfpp)
- [OSV: GHSA-4g9c-3x4p-mfpp](https://osv.dev/vulnerability/GHSA-4g9c-3x4p-mfpp)
- <https://nvd.nist.gov/vuln/detail/CVE-2026-40968>
- <https://github.com/spring-projects/spring-grpc>
- <https://spring.io/security/cve-2026-40968>

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.

## Check whether this affects you

A Match means an installed version is in the affected range above. Most don’t affect the app; agentprime hasn’t analysed this one yet.

- With the agentprime MCP server (<https://api.agentprime.io/mcp>), ask your agent to check the project: `check_lockfile` sends a lockfile, `check_packages` a list of installed packages, and both return the Matches and the upgrades that clear them. `get_advisory` returns this record. Setup: <https://agentprime.io/mcp.md>
- In a browser: <https://agentprime.io/check/> reads your lockfile in the browser, never uploading it.
- Whether it touches your code, with file and line: the Claude Code plugin, <https://agentprime.io/plugin.md>
- As JSON: <https://api.agentprime.io/v1/advisories/GHSA-4g9c-3x4p-mfpp>, or `POST https://api.agentprime.io/v1/match` with your packages (<https://agentprime.io/api.md>)

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The web page: <https://agentprime.io/advisories/GHSA-4g9c-3x4p-mfpp/>. Everything for agents: <https://agentprime.io/llms.txt>.